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hey guys, i have an r32 gtst with a stock internal rb20 running a garrett gt2876r .86 rear housing, internal gate and was wondering if you guys knew of any way to reduce lag, im not seeing full boost untill 4500 rpm, its set to 1 bar, 3 inch turbo back z32 afm fmic and 440cc gtr injectors and a tune are the only mods.

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This ^^^ or buy my HKS 2535 ultimate turbo for a rb20. 230 kw capable plus on pump and more on e85. A 2876r/2540 is a poor turbo in my opinion very mismatched. The compressor wheel is just to big for the little 28 exhaust wheel. There very lazy on a rb25 let alone a rb20. Sell it and buy something else.

This ^^^ or buy my HKS 2535 ultimate turbo for a rb20. 230 kw capable plus on pump and more on e85. A 2876r/2540 is a poor turbo in my opinion very mismatched. The compressor wheel is just to big for the little 28 exhaust wheel. There very lazy on a rb25 let alone a rb20. Sell it and buy something else.

this^^^ , my brother has a 2876r on his rb25, it take till 3500rpm to start pulling, surges like crazy, although he managed a flat 13sec quarter with 12psi which compared to my 2871r highflow at the time on 18psi could do a 13.8 at best.

when it was first bought it was fast, when the cat came off it seemed to pull like crazy but that's when the surge began.

Edited by AngryRBGTX

2535 ultimate? They give away 25-30rwkws to a TD06-20G and from what I have seen of various results dont offer as good response. It hurts the 2535 that it bolts to the std manifold and has an internal gate vs the TD06 setup with manifold and external gate. 20G for a sure 260-270rwkws on 98 with 19 or so psi and 19psi by about 4,300rpm in 4th gear

For sure tdo6-20g is a top turbo aswell. Everyone has there opinions Roy and I know your a rb20 junkie lol so you would know better than me what works on them. But I know the 2535 is a great match for the little rb20. Trent from status/cheuqed tuning seems to like them on rb20s last time I spoke to him.. I also know he is a fan on trust greddy turbos to though. Both good turbos for rb20s. If I ever sell my HKS 2535 I'm keen on buying your T67-25g

Trust turbo or the slightly bigger one for my rb25 ;)

Edited by Joshbigt62r

if i had the spare cash, with out a doubt, but i cant justify $1000 on a turbo to the other half just to improve response, the 20g sounds awesome, but as of yet im not able to upgrade to external gate and aftermarket manifold, might keep that in mind for when cas is a little more available though.

2535 ultimate? They give away 25-30rwkws to a TD06-20G and from what I have seen of various results dont offer as good response. It hurts the 2535 that it bolts to the std manifold and has an internal gate vs the TD06 setup with manifold and external gate. 20G for a sure 260-270rwkws on 98 with 19 or so psi and 19psi by about 4,300rpm in 4th gear

TD06 is a know good thing, but high mount manifold and external gate is probably a little too much for most people when it comes to a daily. (I would personally love an external gate daily but i know most wouldn't :P)

Your current turbo is internally gated. means all the gas go through the mufflers and cat. While externally gated turbos has a large gate welded onto either the exhaust manifold or the turbine housing. They are not legal for street use and heavy fin apply.

There are cheap ways to make your current turbocharger more responsive by going down to a .64 rear and replace the current compressor wheel to some thing like a 71mms 52T.

Hmm.. I have a t04e on my rb20det and looking at upgrading as most people say get rid of the turbo I have.. It has an external gate with no pipe.. Ha -_- but I kind of like hitting boost (when it finally does)

Anyway, I'm thinking of either looking for a different spec for this turbo OR a whole new turbo all together but want to get one that can bolt straight onto std manifold..

As for now I'm plumbing the screamer back, I just paid $1600 for a tune (im an idiot) and tuner told me my turbo is laggy.. (Really!?)

It's off the road until November! So upgrades coming..

First turbo car and I still froth it

Edited by Zrobe

Generally better flow and boost control. The better flow may result in more response or simply better top end with less back pressure...generally its also easier to get them to hold boost. They are my rules of thumb...people could go on for pages sighting instances where the above is not true but they are the fundamentals for doing it. But remains all very setup-parts dependent. A good setup using an internal gate can get great results if parts are all matched

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